Cud chewing is a digestive process found in ruminant animals like cows, sheep, goats, and deer. Ruminants have a four-chambered stomach that allows them to digest tough plant matter through a process of regurgitating and re-chewing their food.
Pigs are non-ruminant animals and have a single-chambered stomach. They do not have the anatomical adaptations or digestive processes necessary to chew cud.